Here \(c\)  is a constant, nominally of order 1, that characterizes the particular time dependent Hamiltonian describing scrambling in the slowly expanding diamonds. Since the typical energy scales in the scrambling Hamiltonian are of order \(H\) , the scrambling bound of [1]} tells us that \(c\)  cannot be too large. Unitarity puts
no constraints on the form of the fast scrambling Hamiltonian, or on the rate to which we add degrees of freedom to itWe caution our readers that these added degrees of freedom are merely being transferred from another subsystem describing evolution of the universe outside the causal diamond. There is no violation of unitarity involved.. Relativity merely tells us that if we look at cosmology from the point of view of a different timelike trajectory then the density matrices predicted by the two models for the common subsystem corresponding to the overlap between diamonds must have the same entanglement spectra. We have used this principle to conclude that the intersection of another FRW trajectory with the past boundary of "our" causal diamond is interpreted as a black hole entering our horizon. Relativity has no constraints on the slow roll era, but becomes important once we have localized objects in the universe. In figure 1, this occurs at the FRW conformal slice halfway between the origin and the position \(\eta _0\)  of the pole in the scale factor describing the dS era.
